1. Field of the Invention
The present invention relates to a portable terminal, and more particularly, to a portable terminal having a structure to minimize interference with a hearing aid.
2. Background of the Invention
In general, a portable terminal serves as a portable device having one or more functions such as voice and video calls, information input/output, and data storage.
As the portable terminal now provides many additional services beside the basic call service, a user can capture photos or moving images, reproduce music or moving image files, play games, receive broadcasting programs, and so on. The portable terminal is implemented as a multimedia player.
Recently, concerns about influences of an electromagnetic wave generated from a portable terminal on a human's body are increasing. And, concerns about interference between a portable terminal and a hearing aid are also increasing. Due to this interference, an electromagnetic wave generated from the portable terminal may result in a mal-operation of the hearing aid.
Under these circumstances, the Federal Communications Commission (FCC) has legislated the Hearing Aid Compatibility (HAC) Act. The HAC Act is being applied to manufacturers for wireless devices such as hearing aids and portable terminals. And, this HAC Act is being widely used around the world.
The HAC Act serves to test and ensure compatibility between a wearer's hearing aid and a portable terminal without interference with each other. A magnetic field generated from the portable terminal is detected and amplified by a T-coil of the hearing aid, and a call sound is transmitted to the wearer. The HAC Act provides a measuring method and a regulation value with respect to a magnetic response of the hearing aid.
Hereinafter, a method for measuring a HAC rating will be explained. The method may include measuring a strength of an electric field generated from the periphery of a receiver 11 of the portable terminal.
Referring to FIG. 1, a receiver 11 is provided at one end of a terminal body 10 of the portable terminal. And, a measuring region 12 is provided so as to measure a strength of an electric field generated from a predetermined region centering around the receiver 11.
The measuring region 12 is formed in a size of 5 cm×5 cm at a height spacing from the terminal body 10 by 1 cm. As shown in FIG. 1, the measuring region 12 consists of nine grids 13. A field strength of each grid 13 is measured by a probe used to measure an electric field. From eight grids 13 excluding the center grid 14, three grids having relatively high field strengths of electromagnetic waves are excluded. Then, a highest field strength of electromagnetic waves measured with respect to the center grid 14 and the rest five grids 13 serves as a peak value to determine a HAC rating. This peak value is required to be less than a predetermined value.
Accordingly, research is actively ongoing so as to reduce a field strength near the receiver 11 when designing and manufacturing portable terminals.